JP5691822B2 - Shaft-type waste pyrolysis furnace and method for pyrolyzing waste materials - Google Patents

Description

The present invention relates to a shaft-type waste pyrolysis furnace and a thermal decomposition method for waste raw materials .

  In recent years, in order to reduce carbon dioxide emissions, as a method for effectively using waste, production of combustible gas that can be used as fuel has been attempted. This waste raw material is a raw material that contains a combination of various wastes such as municipal waste, waste plastic, waste tires, and woody biomass. Since most of these wastes contain carbon, combustible gas is generated when they are put into a pyrolysis furnace and pyrolyzed. Further, a method has been proposed in which this gas is reformed using a reforming furnace to obtain an efficiently usable raw fuel gas. As the pyrolysis furnace, for example, a shaft type pyrolysis furnace, a fluidized bed type pyrolysis furnace, a stoker type pyrolysis furnace, and the like are known.

  The shaft-type pyrolysis furnace is described in Patent Document 1 and Patent Document 2, for example. Patent Document 1 describes a shaft-type furnace that thermally decomposes carbonaceous resources including waste. Patent Document 2 describes a shaft-type pyrolysis furnace having a rectangular cross section. In these shaft-type pyrolysis furnaces, the raw material is introduced from the top of the furnace, falls, and accumulates in the furnace. On the other hand, the product gas generated by the thermal decomposition of the raw material rises in the furnace and is recovered from the upper part of the furnace. The product gas rising in the furnace accelerates thermal decomposition by drying and raising the temperature of the deposited raw material.

  Moreover, the fluidized bed type | mold pyrolysis furnace and the stoker type | mold pyrolysis furnace are described in the patent document 3 and the patent document 4, for example. In the fluidized bed type pyrolysis furnace and stoker type pyrolysis furnace, the raw material is input from the lower part of the furnace, and the product gas is recovered from the upper part of the furnace. In Patent Document 3, in a fluidized-bed or stoker-type thermal reaction furnace, a flow of combustion gas is controlled by providing a barrier with a Yamakasa structure in the furnace to generate an inversion airflow, which is not mixed in the combustion gas. A technique for promoting the reaction of the reaction raw materials is described. Patent Document 4 describes a technique in which a fluidized bed type pyrolysis furnace and a combustion furnace are provided adjacent to each other, and unburnt char generated in the pyrolysis furnace is supplied to the combustion furnace and used as a heat source. Has been. As described above, in the fluidized bed type pyrolysis furnace and the stoker type pyrolysis furnace, a technique for promoting the reaction of the unreacted raw material and improving the heat utilization efficiency of the raw material has been proposed.

Japanese Patent No. 3914474 Japanese Patent No. 4505422 JP-A-5-203130 International Publication No. 99/23431

  On the other hand, in the conventional shaft-type pyrolysis furnace described in Patent Document 1 and Patent Document 2 described above, a raw material that gradually descends in the furnace and a high-temperature product gas that slowly rises in the furnace include Since the raw material is heated by the heat exchange in the counter flow and the thermal decomposition is promoted, the fluidized bed type thermal decomposition furnace (the rising gas flow is very fast) or the stoker described in Patent Document 3 and Patent Document 4 The problem that part of the raw material is entrained in the gas flow and scattered unreacted as in the case of a type pyrolysis furnace (which is easy to drift in a fixed bed and the flow velocity of the drifting part becomes high) has been almost assumed so far However, many studies have not been made on techniques for suppressing such scattering, such as in a fluidized bed pyrolysis furnace. However, as a result of intensive studies by the inventors of the present application, it has been found that unreacted raw materials may be a problem even in a shaft-type pyrolysis furnace.

  FIG. 8 is a schematic longitudinal sectional view of a pyrolysis furnace 10 which is a conventional shaft-type pyrolysis furnace. Referring to FIG. 8, the raw material is input from a raw material inlet 12 provided at the top of the furnace body 11, falls in the space inside the furnace body 11 according to the arrow (white), and accumulates in the lower part of the furnace body 11. . A burner 13 is provided below the furnace body 11. A part of the deposited raw material is combusted by a reaction aid such as one or both of air and oxygen supplied from the burner 13, or water vapor. By this combustion, the temperature of the surrounding raw materials is kept high, and the thermal decomposition reaction of the raw materials proceeds. Alternatively, a high temperature gas such as combustion exhaust gas may be introduced and the sensible heat may be used to advance the pyrolysis reaction.

  On the other hand, the product gas generated by the pyrolysis reaction rises in the space inside the furnace body 11 according to the arrow (black) and is discharged from the gas discharge port 14 provided in the upper part of the furnace body 11. Further, the generated gas is supplied to a reforming furnace or the like through an exhaust duct 15 communicating with the gas discharge port 14. Carbides and residues generated by the thermal decomposition reaction are discharged out of the furnace through a residue discharge port 16 provided at the bottom of the furnace body 11.

  According to the tests by the present inventors, the temperature of the product gas in the pyrolysis furnace 10 is about 1100 to 1200 ° C. near the burner 13, but the temperature decreases in the process of rising between the deposited raw materials, In the vicinity of the surface S, the temperature is about 300 to 500 ° C. An isotherm showing an outline of the temperature distribution in the raw material of the product gas is shown by a thin line in the figure. On the other hand, the temperature of the raw material gradually increases below the deposition surface S, reaches about 100 ° C. when the moisture evaporates, and further increases to reach the reaction temperature. The reaction temperature is, for example, about 250 to 450 ° C. for woody biomass (cedar), about 350 to 500 ° C. for waste plastics (PE, PP, PS), and about 300 to 500 ° C. for waste tires. When the raw material reaches the reaction temperature, the pyrolysis reaction is completed in several seconds to several tens of seconds.

  The inventors of the present application have conducted a test in which a pyrolysis furnace 10 is charged with raw materials including woody biomass, waste plastics, waste tires, and the like and pyrolyzed. As a result, as shown in the figure, the lightweight scattered matter F contained in the raw material is scattered before falling inside the furnace body 11 and is short-circuited to the gas discharge port 14 by being caught in the rising generated gas, as it is. It was found that the product gas was mixed and discharged.

  Here, the lightweight scattered matter F is a raw material having a small specific gravity and a small thickness, such as fluffy waste plastic and powdery woody biomass. In the pyrolysis furnace 10, most of the light weight scattered matter F is scattered before reaching the raw material deposition surface S, and is trapped in the generated gas and shortcuts to the gas discharge port 14. Therefore, a lot of lightweight scattered matter F is not ensured sufficiently for the reaction time, and is mixed with the product gas without being reacted. In this case, when the light scattered F is not sufficiently reacted and discharged to the outside of the furnace, the gasification efficiency is lowered accordingly, and the light scattered F mixed in the generated gas becomes the generated gas. There also arises a problem that the tar content contained is fixed to the inner surface of the exhaust duct 15 as a binder to block the flow path of the product gas. Therefore, in order to stably discharge the generated gas from the pyrolysis furnace 10, the solid matter fixed to the inner surface of the exhaust duct 15 must be periodically cleaned, which causes a reduction in equipment operation rate. .

Therefore, the present invention has been made in view of the above problems, and the object of the present invention is to suppress or prevent discharge of unreacted substances out of the furnace leading to a decrease in gasification efficiency, A new and improved shaft-type waste pyrolysis furnace and waste raw material that can improve the operation rate of the shaft-type pyrolysis furnace by reducing solid matter sticking to the exhaust duct. It is in providing the thermal decomposition method.

In order to solve the above-described problems, according to an aspect of the present invention, a raw material charging port into which a waste raw material containing lightweight scattered matters (hereinafter, also simply referred to as “raw material”) is input, and thermal decomposition of the raw material A furnace body provided with a gas outlet through which the generated product gas is exhausted, and a furnace body that hangs down from the top to the bottom of the furnace body, and drops the raw material from the raw material inlet through a part of the furnace space A shaft-type waste pyrolysis furnace comprising: a partition member that divides a first furnace space for the purpose and a second furnace space for raising the generated gas to the gas discharge port. (Hereinafter simply referred to as “shaft-type pyrolysis furnace” or even simply “pyrolysis furnace”) .

According to such a configuration, in the shaft-type waste pyrolysis furnace, the first furnace space in which the raw material falls and the second furnace space in which the generated gas rises are separated by the partition member, whereby the raw material is separated. It is possible to prevent the light-weight scattered matter included from being short-cut from the raw material inlet to the gas outlet.

The shaft-type waste pyrolysis furnace may further include a measuring unit that measures the deposition height of the raw material inside the furnace body, and an elevating unit that raises and lowers the partition member according to the height of the raw material.

  According to such a configuration, the partition member can be arranged at an optimal position in accordance with a change in the deposition height of the raw material.

The shaft-type waste pyrolysis furnace may further include a reaction aid supply means for supplying the reaction aid to the second furnace space.

  According to such a configuration, it is possible to prevent the tar in the generated gas from adhering to the exhaust duct by increasing the temperature of the discharged generated gas.

In the shaft-type waste pyrolysis furnace, the lower end of the partition member may be positioned above the deposition surface of the raw material inside the furnace body.

  According to such a configuration, the deviation of the flow of the product gas inside the deposited raw material is reduced, and the resistance when the product gas rises in the furnace can be reduced.

In the shaft-type waste pyrolysis furnace, the horizontal sectional area of the second furnace space may be equal to or larger than the sectional area of the exhaust duct communicating with the gas discharge port.

  According to such a configuration, the flow rate of the product gas rising in the furnace can be prevented from becoming larger than the flow rate of the product gas flowing through the exhaust duct, and an excessive increase in pressure loss and wear damage can be prevented.

In order to solve the above-mentioned problem, according to another aspect of the present invention, there is provided a thermal decomposition method of a waste material using the shaft-type waste pyrolysis furnace, wherein the raw material is input from a material input port. Then, the raw material is dropped in the first furnace space and deposited inside the furnace body, the raw material is pyrolyzed to generate product gas, and the generated gas is raised in the second furnace space to discharge the gas. A method for pyrolyzing a waste material characterized in that it is discharged from the wastewater is provided.

As described above, according to the present invention, the reaction of the light scattered matter in the waste material is promoted, thereby reducing the unreacted light scattered matter mixed in the generated gas that leads to a reduction in gasification efficiency. Therefore, solid matter sticking to the exhaust duct is reduced, and the equipment operation rate of the shaft-type waste pyrolysis furnace can be improved.

It is a typical longitudinal section of the thermal decomposition furnace concerning a 1st embodiment of the present invention. It is the II sectional view taken on the line of the thermal decomposition furnace shown in FIG. It is a typical longitudinal section of a thermal decomposition furnace concerning a 2nd embodiment of the present invention. It is a typical longitudinal cross-sectional view of the thermal decomposition furnace which concerns on the 3rd Embodiment of this invention. It is a typical longitudinal cross-sectional view of the thermal decomposition furnace which concerns on the 4th Embodiment of this invention. It is a photograph which shows the test result in the Example of this invention. It is a photograph which shows the test result in a comparative example. It is a typical longitudinal section of the conventional shaft type pyrolysis furnace.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In the present specification and drawings, components having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

(First embodiment)
First, a first embodiment of the present invention will be described with reference to FIG. 1 and FIG.

  FIG. 1 is a schematic longitudinal sectional view of a pyrolysis furnace 100 according to the first embodiment of the present invention. Referring to FIG. 1, a pyrolysis furnace 100 is a shaft-type pyrolysis furnace. In the furnace body 101 of the pyrolysis furnace 100, a raw material charging port 102 into which raw materials are charged, a burner 103 which is a reaction auxiliary supply means for supplying a reaction auxiliary such as one or both of air and oxygen, or water vapor, A gas exhaust port 104 through which product gas is exhausted and a residue exhaust port 106 through which carbides and residues are exhausted are provided. An exhaust duct 105 is provided in communication with the gas discharge port 104.

  Here, the raw material inlet 102 and the gas outlet 104 are each provided in the upper part of the furnace body 101. In the illustrated example, the raw material inlet 102 and the gas outlet 104 are both provided at the top of the furnace body 101, but the present invention is not limited to this, and one or both of the raw material inlet 102 and the gas outlet 104 are provided. However, the upper side surface of the furnace body 101 may be provided. The burner 103 is provided at the lower part of the furnace body 101. Usually, a plurality of burners 103 are installed so that the reaction aid can be uniformly charged into the furnace. Further, instead of or in addition to the burner 103, a high-temperature gas such as combustion exhaust gas may be input. The residue discharge port 106 is provided at the bottom of the furnace body 101.

  Furthermore, the pyrolysis furnace 100 is provided with a partition member 107. The partition member 107 is fixed to the furnace body 101 so as to hang down from the top to the bottom of the furnace body 101. The lower end of the partition member 107 reaches the deposition surface S of the raw material deposited inside the furnace body 101. In addition, the lower end of the partition member 107 may substantially coincide with the deposition surface S as illustrated, or may be positioned below the deposition surface S.

  The partition member 107 divides a part of the furnace space into a first furnace space 108 and a second furnace space 109. The first in-furnace space 108 is a space for allowing the raw material input from the raw material input port 102 to freely fall to the deposition surface S. The second in-furnace space 109 is a space for further raising the generated gas generated in the lower part of the furnace body 101 and rising between the deposited raw materials to the gas discharge port 104.

  In such a pyrolysis furnace 100, the raw material is charged into the furnace from a raw material charging port 102 provided at the top of the furnace body 101 using a conveying means such as a hopper or a conveyor (not shown). The input raw material freely falls in the first furnace space 108 in accordance with an arrow (white), and is deposited on the lower part of the furnace body 101 to form a deposition surface S. A part of the deposited raw material is combusted with one or both of air and oxygen supplied from the burner 103 or a reaction aid such as water vapor to generate a high temperature gas, and the sensible heat is used for the pyrolysis reaction. To advance. In addition, the vapor | steam of reaction aid is supplied in order to prevent the local and rapid temperature rise in the burner 103 vicinity. In addition, when a high-temperature gas such as combustion exhaust gas is introduced, the thermal decomposition reaction proceeds by the sensible heat.

  According to the tests by the present inventors, the temperature of the raw material is normal at the time of charging, but rises due to the combustion gas and the high-temperature product gas as it descends in the furnace, and when the moisture evaporates. 100 ° C. When the temperature of the raw material further rises and reaches the reaction temperature, the thermal decomposition reaction of the raw material proceeds. The reaction temperature is, for example, about 250 to 450 ° C. for woody biomass (cedar), about 350 to 500 ° C. for waste plastics (PE, PP, PS), and about 300 to 500 ° C. for waste tires. When the raw material reaches the reaction temperature, the pyrolysis reaction is completed in several seconds to several tens of seconds.

  The product gas generated by the pyrolysis reaction rises between the deposited raw materials according to arrows (black). The temperature of the product gas is about 1100 to 1200 ° C. near the burner 103, but the temperature is lowered to about 300 to 500 ° C. near the deposition surface S in order to dry and raise the temperature in the process of rising between the deposited materials. To do. An isotherm showing an outline of the temperature distribution in the raw material of the product gas is shown by a thin line in the figure. The reason why the temperature on the second furnace space 109 side is higher is that the flow of the product gas in the raw material is biased toward the second furnace space 109 side. The generated gas further rises in the second furnace space 109 and is discharged from the gas discharge port 104. The product gas discharged from the gas discharge port 104 is supplied to a reforming furnace or the like via the exhaust duct 105. Here, the generated gas in the exhaust duct 105 is sucked using a suction blower (not shown). Therefore, the product gas rising in the furnace is guided to the second furnace space 109 instead of the first furnace space 108.

  On the other hand, carbides and residues generated by the pyrolysis reaction are discharged out of the furnace through the residue discharge port 106. The discharge from the residue discharge port 106 is separated into, for example, carbide and metal and other residues after cooling, and the carbide and metal can be reused.

  In the pyrolysis furnace 100, since the first furnace space 108 where the raw material falls and the second furnace space 109 where the generated gas rises are separated by the partition member 107, the fluff shape contained in the raw material There is little possibility that light weight scattered matter F such as waste plastic or powdery woody biomass will be caught in the generated gas. Therefore, most of the light scattered F falls in the first furnace space 108 like the other raw materials, reaches the raw material deposition surface S, and further rises in temperature in the process of descending the furnace. And pyrolyzed. Therefore, in the pyrolysis furnace 100, it is possible to significantly reduce the lightweight scattered matter F that is mixed and discharged in the product gas without being reacted.

  FIG. 2 is a cross-sectional view taken along line II of the pyrolysis furnace 100 shown in FIG. As shown in FIG. 2, the cross-sectional shapes of the furnace body 101 and the partition member 107 can be various combinations as in the examples (a) to (c), for example. Hereinafter, elements that can be conditions for setting the cross-sectional shapes of the furnace body 101 and the partition member 107 will be described.

  First, the flow rate of the product gas will be described. The inventors of the present application have found that the appropriate flow rate of the product gas discharged from the gas discharge port 104 and flowing through the exhaust duct 105 is about 10 to 30 m / s. If the flow rate of the product gas is higher than this, the pressure loss may increase, or wear damage on the inner surface of the exhaust duct 105 may occur. Therefore, it is desirable to set the cross-sectional area of the exhaust duct 105 so that the flow rate of the exhausted product gas falls within the above range. Similarly, the cross-sectional area (horizontal direction cross-sectional area) of the second furnace space 109 in which the generated gas rises in the furnace of the pyrolysis furnace 100 is also set so that the flow rate of the generated gas does not exceed the above range. Is desirable. Specifically, the cross-sectional area of the second furnace space 109 is desirably equal to or larger than the cross-sectional area of the exhaust duct 105.

  Next, the dropping trajectory of the raw material will be described. The raw material is introduced into the furnace from the raw material inlet 102 at the top of the furnace body 101, and freely falls in the first furnace space. At this time, if the falling trajectory of the raw material is blocked by the partition member 107, there is a possibility that the raw material is deposited unevenly in the lower portion of the furnace body 101. Therefore, it is desirable that the shape of the partition member 107 is set so as not to obstruct the dropping trajectory of the raw material in the first furnace space 108 as much as possible. Specifically, the cross-sectional shape of the partition member 107 is set to make the first furnace space 108 as large as possible while keeping the cross-sectional area of the second furnace space 109 equal to or larger than the cross-sectional area of the exhaust duct 105 as described above. It is desirable to set as follows.

  2A to 2C show examples of the cross-sectional shapes of the furnace body 101 and the partition member 107 set in consideration of the above-described elements. The example of (a) is an example when the cross-sectional shape of the furnace body 101 is substantially circular, and the cross-sectional shape of the partition member 107 is linear. The example of (b) is an example in which the cross-sectional shape of the furnace body 101 is substantially circular, and the cross-sectional shape of the partition member 107 is an arc shape along the furnace body 101. Moreover, the example of (c) is an example when the cross-sectional shape of the furnace body 101 is substantially rectangular, and the cross-sectional shape of the partition member 107 is linear. In addition, it is not restricted to these examples, For example, the cross-sectional shape of the furnace body 101 and the partition member 107 can be various combinations which considered the said element.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG.

  FIG. 3 is a schematic longitudinal sectional view of a pyrolysis furnace 200 according to the second embodiment of the present invention. Referring to FIG. 3, the pyrolysis furnace 200 is a shaft-type pyrolysis furnace similar to the pyrolysis furnace 100 according to the first embodiment. In the following description, points of the pyrolysis furnace 200 that are different from the pyrolysis furnace 100 will be mainly described, and the same components as those of the pyrolysis furnace 100 will be denoted by the same reference numerals and detailed description thereof will be omitted.

  The partition member 207 is different from the partition member 107 of the pyrolysis furnace 100 in that the lower end does not reach the raw material deposition surface S. Since the lower end of the partition member 207 is located above the deposition surface S, there is a gap of a predetermined size between the lower end of the partition member 207 and the deposition surface S. Therefore, the generated gas generated by the thermal decomposition reaction rises between the deposited raw materials to the vicinity of the deposition surface S according to the arrow (black), and passes through the space above the deposition surface S to the second furnace space. Flows into 109.

  Thus, in the pyrolysis furnace 200, when there is a gap between the lower end of the partition member 207 and the deposition surface S, the generated gas rises in the furnace compared to the pyrolysis furnace 100 without this gap. And the pressure loss due to the resistance can be reduced. On the other hand, in the pyrolysis furnace 200, since there is a gap between the lower end of the partition member 207 and the deposition surface S, the lightweight scattered matter F does not reach the deposition surface S and enters the second furnace space 109. It cannot be completely prevented from entering.

  However, the light scattered F is, for example, fluffy waste plastic or powdered woody biomass, and has a thin or powdery shape, so that the reaction time of the pyrolysis reaction is longer than the reaction time of other solid materials. It is often short. Therefore, even if the lightweight scattered matter F contained in the raw material charged into the pyrolysis furnace 200 does not reach the deposition surface S, the temperature rises in the process of descending the furnace to the lower end of the partition member 207, and pyrolysis occurs. The reaction is likely to be complete. Therefore, also in the pyrolysis furnace 200, it is possible to significantly reduce the lightweight scattered matter F that is mixed and discharged in the product gas without being reacted.

  In the pyrolysis furnace 200, if the size of the gap between the lower end of the partition member 207 and the deposition surface S is too large, the light scattering that flows into the second furnace space 109 in a state where the temperature rise is not sufficient. Since the number of the objects F increases, it becomes difficult to sufficiently reduce the unreacted lightweight scattered objects F. Therefore, it is desirable that the size of the gap between the lower end of the partition member 207 and the deposition surface S is set in consideration of the ease of flow of the product gas and the progress of the reaction of the light scattered F.

(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIG.

  FIG. 4 is a schematic longitudinal sectional view of a pyrolysis furnace 300 according to the third embodiment of the present invention. Referring to FIG. 4, the pyrolysis furnace 300 is a shaft-type pyrolysis furnace similar to the pyrolysis furnace 100 according to the first embodiment. In the following description, points of the pyrolysis furnace 300 that are different from the pyrolysis furnace 100 will be mainly described, and the same components as those of the pyrolysis furnace 100 will be denoted by the same reference numerals and detailed description thereof will be omitted.

  The additional burner 310 is a reaction aid supply means for supplying a reaction aid such as air or oxygen, and is provided in the second furnace space 109. Due to the reaction aid supplied from the additional burner 310, a part of the product gas rising in the second furnace space 109 is combusted, and the temperature of the product gas rises. The product gas may contain a small amount of tars generated by thermal decomposition and unreacted lightweight scattered matter F. By increasing the temperature by the additional burner 310, the unreacted material is further reduced, and as a result. As a result, it is possible to prevent the exhaust duct 105 from adhering to the inner surface after being exhausted from the gas exhaust port 104.

  As described above, in the product gas rising in the second furnace space 109, the mixing of the lightweight scattered matter F in the raw material is significantly reduced compared to the conventional case. Therefore, the reaction aid supplied from the additional burner 310 can be made the minimum amount necessary for burning a part of the product gas.

  In the above description, the pyrolysis furnace 300 provided with the additional burner 310 in the pyrolysis furnace 100 according to the first embodiment has been described. Similarly, the pyrolysis furnace 200 according to the second embodiment is added. A burner 310 may be provided.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described with reference to FIG.

  FIG. 5 is a schematic longitudinal sectional view of a pyrolysis furnace 400 according to the fourth embodiment of the present invention. Referring to FIG. 5, the pyrolysis furnace 400 is a shaft-type pyrolysis furnace similar to the pyrolysis furnace 100 according to the first embodiment. In the following description, differences from the pyrolysis furnace 100 in the pyrolysis furnace 400 will be mainly described, and the same components as those in the pyrolysis furnace 100 will be denoted by the same reference numerals and detailed description thereof will be omitted.

  The partition member 407 is not fixed to the furnace body 101, is suspended from a hoisting machine 414 that is an elevating means provided at the top of the furnace body 101, and can be raised and lowered by driving the hoisting machine 414. Different from the partition member 107 of the pyrolysis furnace 100. The partition member 407 is suspended from the hoisting machine 414 using, for example, a wire or a chain. In order to stabilize the lifting and lowering operation of the partition member 407, a guide rail having a shape corresponding to the cross-sectional shape of the partition member 407 may be provided on the inner wall surface of the furnace body 101. The range in which the partition member 407 can move up and down can be set, for example, according to the assumed range of the raw material deposition surface S.

  The weight 411 and the measuring device 412 are measuring means for measuring the deposition height of the raw material inside the furnace body 101. The weight 411 is suspended in the furnace from a measuring device 412 provided at the top of the furnace body 101 and is in contact with the raw material deposition surface S. The measuring device 412 detects the position of the deposition surface S based on the variation in the suspension load caused by the weight 411 contacting the deposition surface S. Note that the measuring means is not limited to this, and the deposition height of the raw material may be measured using, for example, an ultrasonic range finder or a microwave range finder.

  Information on the height of the raw material measured by the measuring device 412 is provided to the control device 413. The control device 413 controls the hoisting machine 414, which is an elevating means, to raise and lower the partition member 407 according to the measured height of the raw material. The control device 413 can be realized as, for example, a computer that executes a program stored in a memory by a CPU (Central Processing Unit) or a control circuit.

  Here, the optimum value of the deposition height of the raw material inside the furnace body 101 varies depending on, for example, the type of raw material, the mixing ratio, the size, the amount of moisture contained, and the like. Further, the deposition height of the raw material varies depending on the processing amount per hour of the pyrolysis furnace 400. In the pyrolysis furnace 400, since the partition member 407 can be moved up and down, even when the deposition height of the raw material fluctuates as described above, the partition member 407 enters too much into the deposited material, It is possible to prevent the member 407 from being too far from the deposited raw material, and to maintain a state in which the partition member 407 functions well.

  The partition member 407 can be moved up and down with the lower end reaching the deposition surface S as shown in the figure, but the lower end as in the pyrolysis furnace 200 according to the second embodiment. It is also possible to move up and down while maintaining a state where there is a predetermined gap between the surface and the deposition surface S. Moreover, in the pyrolysis furnace 400, it is also possible to switch these states mutually. Furthermore, an additional burner 310 similar to the pyrolysis furnace 300 according to the third embodiment may be provided in the pyrolysis furnace 400.

  Next, examples of the present invention will be described. In this example, a test for pyrolyzing raw materials including woody biomass, waste plastic, and waste tires was conducted using a pyrolysis furnace having the same configuration as the pyrolysis furnace 100 shown in FIG.

Here, the woody biomass is a solid matter having a size of about 50 × 150 × 20 mm or less, but a powdery product having a diameter of about 1 mm or less is also obtained by crushing in a stage before being put into the pyrolysis furnace 100. Many are included. Waste plastic is a fluffy waste plastic having a size of about 100 × 100 mm and a thickness of about 0.1 mm or less. The waste tire is a solid having a size of about 200 × 200 × 20 mm or less. Incidentally, the bulk specific gravity of each raw material is wood biomass about 0.2t / ^{m 3,} the waste plastic about 0.07t / ^{m 3,} the waste tire is about 0.4t / ^{m 3.} Moreover, the compounding ratio was a wet mass ratio, and it tested as woody biomass: waste plastic: waste tire = 60: 30: 10.

The pyrolysis furnace 100 used in the present embodiment is a shaft-type pyrolysis furnace having a rectangular section with an area of 0.9 m ^{2 in} the horizontal direction and a height from the burner 103 to the top of the furnace body 101 of 4 m. The above raw materials were mixed and stirred using a forklift, and then charged from the raw material inlet 102 at 0.6 to 0.7 t / h. The temperature in the furnace was kept at 300 to 500 ° C. at the top of the furnace body 101, and for this purpose, the amount of raw material charged and the amount of reaction aid supplied from the burner 103 were adjusted.

  As a result of performing the test under the above conditions, there was little solid matter adhering to the inner surface of the exhaust duct 105, and it was not necessary to clean the inner surface of the exhaust duct 105 even in the continuous test for two weeks. FIG. 6 shows a photograph of the inside of the exhaust duct 105 after two weeks have elapsed in this embodiment. Referring to FIG. 6, it can be seen that in the present embodiment, there is a small amount of solid matter adhering to the inner surface of the exhaust duct 105.

  On the other hand, as a comparative example, a pyrolysis test was performed under the same conditions as in the above examples, using a pyrolysis furnace having the same configuration as the above-described conventional pyrolysis furnace 10. FIG. 7 shows a photograph of the inside of the exhaust duct 15 after one week in this comparative example. Referring to FIG. 7, it can be seen that in this comparative example, there are more solids fixed to the inner surface of the exhaust duct 15 than in the above embodiment. As a result, the continuous test in the comparative example required cleaning of the inner surface of the exhaust duct 15 after one week.

  From the above results, by using the pyrolysis furnace according to the embodiment of the present invention, it is possible to reduce sticking of solid matter to the exhaust duct and improve the equipment operation rate of the shaft-type pyrolysis furnace. It can be said that has been demonstrated.

  The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious that a person having ordinary knowledge in the technical field to which the present invention pertains can come up with various changes or modifications within the scope of the technical idea described in the claims. Of course, it is understood that these also belong to the technical scope of the present invention.

100, 200, 300, 400 Pyrolysis furnace 101 Furnace body 102 Raw material inlet 103 Burner 104 Gas outlet 105 Exhaust duct 107, 207, 407 Partition member 108 First furnace space 109 Second furnace space 310 Additional burner 411 Weight 412 Measuring device 413 Control device 414 Hoisting machine F Light weight scattered matter S Sedimentation surface

Claims (6)

A furnace body provided with a raw material input port into which waste raw materials including lightweight scattered matter are input, and a gas exhaust port through which generated gas generated by thermal decomposition of the raw material is exhausted,
A part of the furnace space is suspended from the top to the bottom of the furnace body, the first furnace space for dropping the raw material from the raw material input port, and the generated gas to the gas discharge port. A partition member that is divided into a second furnace space for raising;
A shaft-type waste pyrolysis furnace comprising: Measuring means for measuring the deposition height of the raw material inside the furnace body;
Elevating means for elevating the partition member according to the height of the raw material;
The shaft-type waste pyrolysis furnace according to claim 1, further comprising: The shaft-type waste pyrolysis furnace according to claim 1 or 2, further comprising a reaction aid supply means for supplying a reaction aid to the second furnace space. The shaft-type waste pyrolysis furnace according to any one of claims 1 to 3, wherein a lower end of the partition member is positioned above a deposition surface of the raw material inside the furnace body. . The shaft type according to any one of claims 1 to 4, wherein a horizontal cross-sectional area of the second furnace space is equal to or larger than a cross-sectional area of an exhaust duct communicating with the gas discharge port. Waste pyrolysis furnace. It is the thermal decomposition method of the said raw material using the shaft type waste thermal decomposition furnace of any one of Claims 1-5,
The raw material is introduced from the raw material inlet,
Dropping the raw material in the first furnace space to deposit in the furnace body;
Pyrolyzing the raw material to produce the product gas,
The method of pyrolyzing waste materials , wherein the product gas is raised in the second furnace space and discharged from the gas discharge port.